Thanks for the quick response. THis is the only rotted out area in the cowl and overall it is very clean. The shot above is the worst spot on the entire car. I am looking for a fix that will be relatively permanent. This car is garaged in AZ and not a daily driver, so if I can stop the spread it should last for a long time. What you can't see is the the other hole going into the interior, so if it do get caught in the rain, I really do have extra drain holes (but I will need wear my hip waders while driving
). I may cut the rotted metal out, treat with a rust blocker, and use a fiberglass patch to seal in the holes.
At some point, I may tear back into this area, but other pieces may take priority...